package com.zsw.handler;

import lombok.extern.slf4j.Slf4j;
import org.springframework.security.authentication.ReactiveAuthenticationManager;
import org.springframework.security.core.Authentication;
import org.springframework.security.oauth2.common.OAuth2AccessToken;
import org.springframework.security.oauth2.common.exceptions.InvalidTokenException;
import org.springframework.security.oauth2.provider.OAuth2Authentication;
import org.springframework.security.oauth2.provider.token.TokenStore;
import org.springframework.security.oauth2.server.resource.BearerTokenAuthenticationToken;
import reactor.core.publisher.Mono;

/**
 * @Description 基于WEBFLUX的过滤器，由于gateway使用长连接web，故不能使用springboot-starter-web
 * @Author sandman
 * @Date 2020-08-14
 */
@Slf4j
public class JwtAuthenticationHandler implements ReactiveAuthenticationManager {


    private TokenStore tokenStore;

    public JwtAuthenticationHandler(TokenStore tokenStore) {
        this.tokenStore = tokenStore;
    }

    @Override
    public Mono<Authentication> authenticate(Authentication authentication) {
        return Mono.justOrEmpty(authentication)
                .filter(a -> a instanceof BearerTokenAuthenticationToken)
                .cast(BearerTokenAuthenticationToken.class)
                .map(BearerTokenAuthenticationToken::getToken)
                .flatMap((accessToken -> {
                    log.info("accessToken is :{}", accessToken);
                    OAuth2AccessToken oAuth2AccessToken = this.tokenStore.readAccessToken(accessToken);
                    //根据access_token从数据库获取不到OAuth2AccessToken
                    if (oAuth2AccessToken == null) {
                        return Mono.error(new InvalidTokenException("访问令牌无效，请检查"));
                    } else if (oAuth2AccessToken.isExpired()) {
                        return Mono.error(new InvalidTokenException("访问令牌已过期，请重新获取令牌!"));
                    }

                    OAuth2Authentication oAuth2Authentication = this.tokenStore.readAuthentication(accessToken);
                    if (oAuth2Authentication == null) {
                        return Mono.error(new InvalidTokenException("访问令牌无效!"));
                    } else {
                        return Mono.just(oAuth2Authentication);
                    }
                })).cast(Authentication.class);
    }
}
